Light quantity control device

Abstract

A light quantity control device includes: a bottom board having an opening; a first blade, a supporting blade and a second blade linearly moving in opposing directions and controlling light quantity passing through the opening; and a driving lever connected to the set of blades and driving the set of blades by rotation of the driving lever. The driving lever rotates within degrees centering on a phantom line A passing through a rotational center of the driving lever and being parallel with the moving directions of the blades.

1. A light quantity control device comprising:
 a bottom board having an opening; 
 a set of blades linearly moving in opposing directions and controlling light quantity passing through the opening; and 
 a driving lever connected to the set of blades and driving the set of blades by rotation of the driving lever, 
 wherein the driving lever stops at least one partway position between one end and the other end of a rotational range thereof the driving lever, and the driving lever lies within 90 degrees centering on a phantom line passing through a rotational center of the driving lever and being parallel with the moving directions of the blades, wherein the driving lever is capable of being along the moving directions of the blades, 
 wherein a state of the opening in the partway position is a fully closed state. 
 
   
   
     2. The light quantity control device according to  claim 1 , wherein:
 the set of blades each has a slot engaging with a pin formed in the driving lever, and 
 the slot is formed in a widthwise direction of at least one of the blades. 
 
   
   
     3. The light quantity control device according to  claim 1 , wherein at least one of the blades has a slot engaging with a pin formed in the driving lever, wherein the slot has a substantially L-shape.